In that circuit, the Comparator is just there to square up the pulse, correct?

I think I'm going to try the following idea, one conditioner per gate (which doesn't have the common gate bus being a constant voltage problem) with the exception of the comparator, each one going through a diode to a common bus which is THEN squared up by the comparator.

Yes, it's brute force But at this point if it works, that'll be sufficient.

sorry, if i tell you things that have already been covered, i just did not read the complete thread.

so this is what i did to get triggers from a 4017 sequencer:

i just used an AND gate to combine the gates from the 4017 with the incoming clock.
unfortunately it was not that simple, since sometime double triggers occured. this was due to the propagation delay of the ICs used for the actual sequencer.

so i added a delay to incoming clock right before the AND gate to get rid of this.

below you see the schematic of what i currently have (4017 gates from above, original clock from left). BTW you might get away with just one AND gate, i think the 1st one with the pull down resistor is a leftover from earlier stages of the development. it might not be needed (but hey, there are more than just one AND gate on these CMOS ICs anyways...)

Conditioning the gate as well also seems like a good idea; better up and down and there's less opportunity for the overlap.

I'll give this a shot. I also came up with a neatly symmetric way to put the trigger conditioning from Ken Stone onto stripboard in a compact fashion, but I could do with not using up all those diodes....

Is there anything special about the BC850? Or should I be able to get by with any of the various NPN transistors I have?

I can see the clock delay (though I had to increase the cap to 220nF to get it to a point where there was almost no overlap...possibly a bigger trimmer would have done it too though). But I was still getting double triggers, even putting the gate back to directly into the AND gate.

But... As soon as I placed my scope across the gate to ground, suddenly the problem went away. SO I put 100K from the gate input into ground, and now it's working.

So maybe all those pull ups and pull downs are why yours is working, minus

To be clear:

What's working is a clock delay per Fonik's schematic, gate directly into the AND with 100K to ground at that point.

Now I just have to get this onto the stripboard--shouldn't be a huge problem, there's space left

I'm just a little disappointed I didn't get to use my fancy trigger conditioning though

2013-03-09_20-37-46_269.jpg

Description:

4 trigger conditioning circuits into two common busses (which would have been joined into one had I completed this). Thankfully, none of that is actually soldered in, I was just trying to see how well it would fit....

Excellent news! I might have to do a stripboard diagram at some point for a trigger sequencer.

I've been thinking about building the Thomas Henry Superseque for some time. I'll probably incorporate this valuable research into the design so I can trigger drums too.

I think those pull down resistors were a result of too much time in the Lunetta forum. The resistors I have on the CLOCK input to the NAND gates aren't needed, but maybe the ones coming from the switches are. If the switches in a channel weren't turned on, then surely the NAND input would be left floating? Doesn't matter. It's only a few extra 10K resistors. I'll know where to salvage some from when I run out in the middle of the night!

Yes, on a step where the gate switch is open, I'm guessing that the diodes on the other connections basically leave the input floating. So of COURSE it is able to let the clock through. As I was testing all this, there were times at other points in the circuit where I'd let an input float and it was always letting the other side of the AND or NAND through at that point.

So I have the 40106 and other circuitry safely ensconced on my stripboard, albeit somewhat ugly thanks to it being added on. And I had to tweak the trimmer for 9V rather than 15V operation. but other than that, it's beautiful.

So is mh11 a name for the module as a whole as opposed to the VCPS-8 PCB? It's obvious where the MH comes from, but I have one of the VCPS boards near the top of my backlog and I'm curious if I'm actually building the same thing....

(The baby stripboard was for a more portable self-contained unit which I can carry around with my cigarlab/soundlab box...)

So is mh11 a name for the module as a whole as opposed to the VCPS-8 PCB? It's obvious where the MH comes from, but I have one of the VCPS boards near the top of my backlog and I'm curious if I'm actually building the same thing....

almost.

for the production module i skipped the grey encoding of the patterns (using just plain hex), but i incorporated all the improvements, like the 'ADC ignition system' (TM) and the clock delay trimmer (refer to the thread)._________________
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I'm capable of building the circuit, but I'm confused. To connect this to a synth with a cv and gate input (such as a modified Korg Monotron), I need to connect BOTH the CV and the GATE (labeled pulse out or whatever in the schematic), right?
The gate from the sequencer is telling the synth to turn the notes on/off (thus why its constant v, not through the pots), and the CV tells the synth which pitch to play. I think?

So if I wanted to connect a 3-way switch on each output (step off, step on, reset at that step), would I do it at the CV or pulse outs outputs?

I'm assuming by "pulse outs" you mean the individual steps coming out of the 4017s, and if so then yes, that's what you would connect to the center of your on-off-on switch. Then one position would be "send the gate", off would be off, and the other position would be "send a reset".

Wish I'd thought of that before building my Baby-8, it would have been much easier to work with than the rotary I chose

Thanks for the reinforcement.
One more question...Could this simple 4017+555 sequencer be powered with one 9v battery? And if so, how would I go about making a 9volt batttery regulator (so that I could adjust the voltage, with a linear potentiometer perhaps, down from 9volts). I guess I want the ability to somewhat tune the outputs, and also to make sure its not too hot for the synth.

I'm not entirely sure I understand your question. Going back to the stripboard layout at the very very start of all this, yes, of course it can be powered with a 9V Battery That's what I have done with mine.

I would assume the 16 step variant would be able to as well, though presumably it might go through batteries more rapidly.

As for limiting the output, that's where I'm unclear. Normally each step of the 4017 output drives a pot acting as a voltage divider which sets the CV level for that step. Each of those goes through a diode to a common bus--diode so they don't interact with each other.. In the scenario with the switch, then the side of the switch corresponding to "on" would go to the pots.

Are you working with Synths that can't take up to 9V input on their voltage control? I have a 15V modular so it has absolutely no problems, and I've also used this with a +/- 9V Soundlab mini-synth which similarly has had no problems.

I would see two possibilities here.

1) connect the outputs to a transistor driver where the drive voltage was set to whatever you were looking to be your maximum.

2) send the CV output through a scaling op amp that limits the maximum (I could see this being pretty easy to adjust with a pot).

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